Injection with DI

[vasiliykai]

Hi!
Injection with DI pass empty lists into constructor instead of expected null parameteres. Because of that default allowed tags not initialize. Problem can be solve in DI registration. But this this is unexpected behavior.
Thank you!

[mganss]

Do you have an idea how this could be solved in a backwards compatible manner?

[tiesont]

I think you'd need to verify if this happens with all DI frameworks, or just specific versions. If it's everything, that would imply that is expected behavior.

[vasiliykai]

User of library no need to know about its realization. Allowed tags must works on default. And becouse of that anyway it is unexpected behavior

[vasiliykai]

You can change the constructor like that:
public HtmlSanitizer(...)
{
AllowedTags = new HashSet(string.IsNullOrEmpty(allowedTags.FirstOrDefault()) ? DefaultAllowedTags : allowedTags ,
StringComparer.OrdinalIgnoreCase);
...
}

[mganss]

Perhaps we could treat the special case where all arguments are empty lists in the same as when they are all null.

[vasiliykai]

Also you can add default contructor without parameters and configure it to call original constructor with required parameters. DI always call default contructor by default

[mganss]

Are you sure about this? Do you have a link to documentation about this? AFAIK it will try to call the constructor having the most resolvable arguments.

[vasiliykai]

Yes, you right. Maybe all you can is to make breaking-change patch and make decisions about allowed tags more explicit. You can improve convenience by give users easily way to add their tags to default tags, as example... Or you can add method like ResetAllAllowsToDefautl(). I really dont know which way is better. If i have some ideas i wrote you

[mganss]

You can easily manipulate the default sets through DefaultAllowedTags etc.

[mganss]

See also #220.

[mganss]

I've fixed this by treating the special case where all arguments are empty the same as if they were all nulls.